movement; and his active movements are less jerky-more steady and continuous."

In the case of A, it was noted that on D. 29 his resistance to arm movements was much stronger than in early days. In the case of A also, the hand grip was much stronger at this period than earlier: one or two of his reflexes seemed to develop later than in B; and the coincident contraction of opposing muscles seems also to have appeared later.

By D. 64, however, A showed the same condition as that indicated in the notes of B the corresponding day, quoted above.

REFLEXES AND INSTINCTS.

It is of special interest to note the evidences at this early stage of the activities which apparently blend reflexes and instincts.

REFLEX OR INSTINCT: THE SUCKING IMPULSE.

The process of food getting if carefully studied impresses on one the difficulty of drawing a hard and fast line between reflexes and instinctive actions.

Dearborn1 refers to sucking as a reflex. Stern calls it an instinct2. Miss Shinn3 after writing "Sucking, if an instinct and not a reflex' comes down on the side of instinct, partly because it ceases with satisfaction and partly because it can be initiated without external stimulus. She adds that as the child grows older, sucking loses the traits of a reflex that it at first promised, and becomes purely voluntary.

Preyer1 after remarking that 'Intellect' must be excluded from the process of sucking, seeing that a child without a cortex sucks, argues that sucking is not a pure reflex, in that a babe sucks only when it is hungry. Similarly Koffka, mentioning among other things this characteristic of an instinct, namely that 'there must be a particular state of the organism as a whole,' says that this is true of sucking which he accordingly groups with instincts5.

My own observations suggest the existence of an evanescent reflex within an instinctive system. For observations on the first day (and

1 Op. cit. p. 198.

2 The Psychology of Early Childhood, p. 70.

3 Notes on the Development of a Child, 1, p. 386.

4 The Senses and the Will, p. 258.

The Growth of the Mind, p. 87. Koffka later argues that reflexes are to be explained as instincts, instead of vice versa (p. 188).

frequently later) show that B would suck his thumb when he would not suck the breast. During later weeks-as mothers well know-a child will often suck its thumb when replete: but by then it may be argued that sucking has become a habit. The significance of observations on the first day or two is that the reflex seems to occur before a 'habit' based on the instinct could possibly be set up. Thus:

D. 1: "B sucked his right thumb even though he would not seriously tackle the breast." There was practically no feeding on D. 1, yet so frequent sucking of thumb or fist, that I made the note: "Only right hand sucked so far."

D. 2: "Though on one occasion he 'nursed well' he would not take food properly most of the day, and he was (forcibly) spoon fed several times by the nurse."

Dearborn also mentions that his daughter would not nurse the first day, yet "suction on the fingers and the side of the fist was very strong and lively from the first morning."

The contention therefore of Preyer that sucking is an instinct because it only takes place when the child is hungry, cannot be upheld.

The fact that it takes place so often in sleep is also in favour of its classification as a reflex, as is also the fact that a child without a cortex will suck.

There would seem then to be a reflex in the sense that the placing of an object of suitable shape, temperature and softness in the mouth produces sucking, even when food is not sought or desired. And this reflex is made use of in the wider instinctive process of food getting involving groping also for the breast; and undoubtedly the state of hunger is the usual stimulus at early stages at least of sucking actively. Later on the craving for the reflex activity is intelligently satisfied by placing the thumb intentionally in the mouth-as a craving for the release of the sneezing reflex may be produced by deliberately looking at the sun. This deliberate satisfying of the impulse sometimes seems to establish a habit or species of secondary reflex, which in some children is persistent for several years, and which even shows traces in some adults.

Its continued association with the craving for food even at the later stages of infancy is shown by the fact that a child will pacify itself when hungry by sucking its thumb vigorously.

D. 157: "Crying, very hungry. Soothes himself for a time with his thumb, and does not take it out at once even when put close to the breast." Similarly on D. 162.

This child also, about this period, on being lifted in the night for a feed, frequently slipped his thumb into his mouth at once, before waking.

THE DISTINCTION BETWEEN REFLEXES AND INSTINCTS.

It has not been my purpose here to argue that there is no distinction between reflexes and instinctive actions, and even if we could not draw a definite line of division between them, the two names would be needed. For in psychology, where all parts of the whole mind are convenient but abstract conceptions, it is necessary to indicate by separate names, actions or qualities which stand out at stages in a continuous series even where no absolute break can be made.

It is, rather, my desire to illustrate some of the grades in the series from a purely mechanical and isolated action-the (theoretically) 'simple reflex' to the highly complex volitional actions: to show resemblance between actions usually classified as reflexes and others usually called instincts; and to emphasize the fact that reflexes may be linked up with and included in the main activities of instinctive systems.

SUPPOSED MARKS OF A REFLEX.

The difficulty of absolute separation of the two concepts is brought out if we examine some of the criteria offered for distinguishing reflexes from instincts.

(a) First, an instinct is said to be the 'reaction of the whole organism,' while a reflex is always a 'partial reaction1.'

Now we know that a reflex is dependent partly on the general conditions of the organism as a whole. It is even used sometimes as a test of general nervous condition. The nature of the reflex response is, at least in a negative sense, determined by the inhibiting effect of the cortex. But further, we have seen reason to believe, as in the case of the hand-grasp reflex, that an emotional state or even mild excitement may cause that reflex to take place when it would not do so otherwise, or it may intensify its strength. In other words, that the general condition of the whole organism may be one factor in producing a reflex, just as a more limited facilitation by supplementary sensory stimulations may be one factor, and an essential one as the physiologists have shown.

On the other hand, even an instinctive response is hardly a reaction of the whole organism in the fullest sense. In flight under fear the instincts. of sex and acquisitiveness are in entire abeyance, and the intellectual 1 E. B. Titchener, Text Book of Psychology, II, p. 464; McDougall, Outline of Psychology, p. 56.

interests of life-however powerful normally-are entirely inactive. One may defend this idea of a response of the whole organism better by reference to energy, and its concentration on the main end in view. "That is the type of the total reaction," writes McDougall. "The vital energies of the whole organism are concentrated upon the task in hand1.” And even to this I should prefer to add "the main vital energies" for who can say whether some special energies are not correlated with the activities and interests which are quiescent at the moment?

An instinct then may be said to be a response of the whole organism only in the sense that no main section of the nervous system is entirely cut off from the more localized parts concerned with the action or from the possibility of influencing that action. And this may be true of a reflex. (b) A second characteristic of the reflex is said to be the absence of any 'profiting by experience2.'

"The whole process is immediate and incapable of modification3.” There is however some improvement in the sucking and grasping reflexes; though it is, of course, difficult to say how far this is due merely to ripening and how far to experience. The extension of the winking reflex to things seen approaching is properly a result of association of a new stimulus with other appropriate stimulus. And to the citing of such improvements or extensions the reply may well be made that in so far as there is learning or modification as the result of consciousness, there is something more than a reflex involved.

This, as I understand it, is McDougall's reply when faced with the example of a conditioned reflex shown by Pavlow's dog, when the bell had become associated with food and hence caused saliva to flow1.

It is, I think, perfectly legitimate to contend that such 'reflexes' are more than reflexes. I am at present simply concerned to point out that some acknowledged' reflexes are either capable of development, or at least of complication in that they become inextricably linked up with higher processes. This sphere may be extended by associationas in the winking reflex and the saliva flow. They may improve with experience, as in the grasping reflex, either by mere improved efficiency of the mechanism, or by complication with the beginnings of voluntary

1 McDougall, Outline of Psychology, p. 57.

2 Ibid. p. 54.

3 W. H. R. Rivers, Instincts and the Unconscious, p. 28. Dr Rivers just afterwards contrasts reflexes with conscious processes, so he may not have intended to include all reflexes under this statement.

4 McDougall, op. cit. p. 55.

movement. In the development of voluntary movement, there is at least learning through reflexes.

Finally, reflexes may be linked with instinctive processes as in foodgetting and sex, so as to be almost inseparable if not psychologically indistinguishable. We need not then accept either of the two extreme opinions as to the nature of the long series of useful actions, such as the solitary wasp goes through in providing for the next generation— on the one hand that they are merely a series of reflex actions, and on the other that the whole process is instinctive. For a third view is possible, namely, that the whole process is one in which many genuinely reflex responses are embedded in a wider process, partly guided by consciousness.

(c) A third characteristic of the reflex is said to be its Inevitability. We have seen that the occurrence of some reflexes is dependent upon the general condition of the organism, and sometimes perhaps upon the relative novelty of the stimulus, or rather the recency with which the stimulus has been applied. The eye-blink which occurred on the first loud clap of the hands might cease on the third or fourth. A sneeze produced once or twice by looking at the sun, cannot be produced a third or fourth time without a considerable interval. If it is replied that this is mere fatigue, then variability of this type in instinctive process, and even in intelligent interests, might be attributed to fatigue. Apart from the influence of fatigue (as when the speeding up of the stimuli of the eye-blink results in intermittent misses of the reflex response) we found inexplicable variability in the eye-blink response to sudden. noises.

Certainly, however, the typical reflex lacks that 'persistency with varied effort' characteristic of higher types of action.

There is, of course, the well-known example of the decerebrated frog, who will scratch his left side (irritated by acid) with his left foot: and then if the left foot is held up, will, after a pause, use the right foot. But as the physiologists themselves point out, the continued stimulation would by summation result in an overflow from the left side to the right side, and so produce a reflex1; or as McDougall suggests, in an animal at this low stage the brain (as certainly is the case in some animals at a lower level) may not be essential for consciousness, and the frog's action may be conscious and 'purposive2.'

(d) A fourth mark of the reflex is said to be the nature of its dependence on external stimulus. It "does not show that preparation 2 Op. cit. p. 49.

1 Starling, Human Physiology, 5th edition, p. 606. Med. Psych. VII

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